South African all-rounder Jacques Kallis resisted calls on Wednesday to rethink his decision to quit as Test vice-captain after being left out of the host's squad for the Twenty20 world championships.

Cricket South Africa had asked Kallis, the country's highest ever scorer in Test cricket, to reconsider his move but acknowledged in a statement that there was now no turning back.

"When Jacques accepted the vice-captaincy two years ago at the start of Mickey Arthurs term as national coach, it was always on the basis that he would see how he enjoyed the extra responsibility of the position and he would review it after a suitable period," CSA chief executive Gerald Majola said.

"Jacques has now decided that he wants to concentrate on his own game. Our discussions were entirely cordial and constructive and it is only right that we accept his decision."

Kallis had reacted furiously to his axing from the squad. Selectors claimed he needed to rest ahead of the Proteas busy schedule in the coming season.

Reports in the South African media on Wednesday had suggested Kallis might be called up to replace injured batsman Loots Bosman. However it was later announced that fast bowler Andre Nel would take his place.

Kallis was quoted in the statement as saying he would "always be willing to help others, in reference to his role as senior batsman in the Proteas squad.